Thermal characterization of PCM
Scientists from the ZAE Bayern develop measurement methods to characterize PCM materials in application-oriented samples. The project PCM Metro aims to a better understanding of quantity-dependent phenomena compared to standard laboratory procedures.
|Project status||Project completed|
|Type of storage||Latent heat|
|Project duration||July 2013 until June 2016|
The PCM technology holds great potential to increase the thermal inertia of buildings in critical temperature ranges. Currently there is a gap in metrology between calorimeters for very small amounts of sample and test rooms as well as demonstration objects for complete PCM systems.
The properties of PCM materials are usually determined in the laboratory using small samples. In many cases, however, it would be necessary to work with practical amounts, for example, to investigate specific storage geometries. In addition, the behaviour in hypothermia is often depending on quantity. Inhomogeneities in small samples can affect readings.
Studies on materials, components and parts
New calorimetric measurement methods should allow the determination of the heat storage capacity of large PCM samples. This allows the study of PCM composite materials macroencapsulated PCM and PCM - building components. Furthermore, the researchers want to develop methods that can determine the dynamic behavior of PCM components. It would allow to characterize the dynamic behavior of a component during development, without equipping a complete test room.
The project thus closes a metrological gap and provides scientific background for the development of industrial standards. Another objective is the dissemination of results and implementation of the findings in national and international standards and guidelines.
The basic approach of the measurement methods which will be investigated in the project is to subject a sample to a controlled temperature programm and to record the resulting heat flow. Measurement equipment will be either newly built or existing equipment will be modified so that the heat storage capacity and the dynamic thermal behavior of the samples containing PCM can be determined.
Rate PCM products reliably
By the development of calorimetric measurement methods for the determination of the heat storage capacity of large samples as well as by the development of measurement methods for the determination of the dynamic thermal behavior of PCM components and PCM building elements, products that are available on the market can be reliably evaluated and the research and development of new products can be optimized at different levels. Therefore, the new measurement methods are of strong interest for the PCM manufacturers to remain competitive and to optimize the development of products at different levels relating to time and cost expenditures. Additionally, with increasing the quality of the offered products the society's trust in the PCM technology will be increased, which facilitates the commercialization of PCM and might possibly also extend the area of application.
Work Package 1: Development of calorimetric measurement methods for the determination of the heat storage capacity of large samples, i.e. for macroencapsulated PCM, PCM composite materials, application-typical PCM sample quantities and PCM-building elements
Work Package 2: Development of measurement methods to determine the dynamic thermal behavior of PCM components and PCM building elements for direct evaluation of the behavior in buildings. Possible samples are for example PCM components and PCM building elements such as PCM cooling ceilings, segments of facades and walls etc.
Work Package 3: Dissemination of results and implementation of the findings in national and international standards and guidelines
Publications on this project
Verification of a T-history installation to measure enthalpy versus temperature curves of phase change materials; A. Lazaro, E. Günther, H. Mehling, S. Hiebler, J.M. Marin and B. Zalba, Meas. Sci. Technol. 17 (2006) pp 2168–2174. doi:10.1088/0957-0233/17/8/016
Determination of the enthalpy of PCM as a function of temperature using a heat-flux DSC - A study of different measurement procedures and their accuracy, C. Castellón, E. Günther, H. Mehling, S. Hiebler, L. F. Cabeza, Int. J. Energy Research 32 (2008) 1258-1265
Enthalpy of Phase Change Materials as a Function of Temperature: Required Accuracy and Suitable Measurement Methods, E. Günther, S. Hiebler, H. Mehling, R. Redlich, Int. J. Thermophys. (2009) 30:1257–1269, DOI 10.1007/s10765-009-0641-z
Latent heat storage in buildings; H. Mehling, BINE Themeninfo I / 2009
Determination of the heat storage capacity of PCM and PCM-objects as a function of temperature; E. Günther, S. Hiebler, H. Mehling; Proc. of ECOSTOCK, Stockton USA, 2006
Enthalpy of phase change materials as a function of temperature – required accuracy and suitable measurement methods, E. Günther, H. Mehling, S. Hiebler, R. Redlich, Proc. of 18th European Conference on Thermophysical Properties, Pau, France 31 Aug-4 Sep 2008
Measurement of the enthalpy of PCM, E. Günther, S. Hiebler, H. Mehling, Proc. of 11th International Conference on Thermal Energy Storage, June 14th – 17th, 2009, Stockholm
Heating and cooling using a combination of several TES technologies in the new R&D building of the ZAE Bayern in Würzburg, F. Klinker, H. Weinläder, H. Mehling, S. Weismann, D. Büttner, H.-P. Ebert, E. Lävemann, T. Ebert, W. Jensch, 12th International Conference on Energy Storage (INNOSTOCK 2012)
Current research at the ZAE Bayern – Testing, data representation and modelling of PCM; H. Mehling, H.-P. Ebert, F. Hemberger; IV Thermal Mass Workshop, Clearwater Beach, Florida, USA, 4th and 5th December 2010
A study of different measurement and evaluation methods; H. Mehling, S. Hiebler, E. Günther, F. Hemberger; 19th European Conference on Thermophysical Properties, August 28th – September 1st 2011, Thessaloniki, Greece